Tasks connected with tooltip.

Here I have included next tasks:
[MAGN-4765](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-4765) DUI: If Desc and pic missing from tooltip - remove the top part
[MAGN-4615](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-4615) DUI: Some tooltips' margins are off
[MAGN-4672](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-4672) DUI: Tooltip content for inputs and outputs
[MAGN-4379](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-4379) DUI: Change the tooltip fade out time to 0.5 seconds

At every part I made comment.
So, if node is constructor, we should show its' `className`.